[PATCH 15/27] drm/radeon: add general purpose fence signaled callback

[j.glisse at gmail.com]

From: Christian König <deathsimple at vodafone.de>

Should be used to free resource that are protected by a fence.

Signed-off-by: Christian König <deathsimple at vodafone.de>
Reviewed-by: Jerome Glisse <jglisse at redhat.com>
---
 drivers/gpu/drm/radeon/radeon.h       |    8 ++++-
 drivers/gpu/drm/radeon/radeon_fence.c |   50 +++++++++++++++++++++++++++++---
 2 files changed, 52 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index fbbbc5a..11cceb3 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -259,7 +259,6 @@ struct radeon_fence_driver {
 	wait_queue_head_t		queue;
 	struct list_head		created;
 	struct list_head		emitted;
-	struct list_head		signaled;
 	bool				initialized;
 };
 
@@ -274,6 +273,10 @@ struct radeon_fence {
 	/* RB, DMA, etc. */
 	int				ring;
 	struct radeon_semaphore		*semaphore;
+
+	/* called when fence is signaled */
+	void	(*signal_callback)(struct radeon_device *rdev, void *data);
+	void	*callback_data;
 };
 
 int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring);
@@ -289,6 +292,9 @@ int radeon_fence_wait_empty(struct radeon_device *rdev, int ring);
 struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence);
 void radeon_fence_unref(struct radeon_fence **fence);
 int radeon_fence_count_emitted(struct radeon_device *rdev, int ring);
+bool radeon_fence_set_signal_callback(struct radeon_fence *fence,
+                                      void (*callback)(struct radeon_device *, void *),
+                                      void *data);
 
 /*
  * Tiling registers
diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
index 2d13843..c58660a 100644
--- a/drivers/gpu/drm/radeon/radeon_fence.c
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -83,7 +83,8 @@ int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence)
 	return 0;
 }
 
-static bool radeon_fence_poll_locked(struct radeon_device *rdev, int ring)
+static bool radeon_fence_poll_locked(struct radeon_device *rdev, int ring,
+				     struct list_head *signaled)
 {
 	struct radeon_fence *fence;
 	struct list_head *i, *n;
@@ -110,7 +111,7 @@ static bool radeon_fence_poll_locked(struct radeon_device *rdev, int ring)
 		i = n;
 		do {
 			n = i->prev;
-			list_move_tail(i, &rdev->fence_drv[ring].signaled);
+			list_move_tail(i, signaled);
 			fence = list_entry(i, struct radeon_fence, list);
 			fence->signaled = true;
 			i = n;
@@ -120,6 +121,20 @@ static bool radeon_fence_poll_locked(struct radeon_device *rdev, int ring)
 	return wake;
 }
 
+static void radeon_fence_process_signaled(struct radeon_device *rdev, struct list_head *signaled)
+{
+	struct radeon_fence *fence;
+	struct list_head *i, *n;
+
+	list_for_each_safe(i, n, signaled) {
+		fence = list_entry(i, struct radeon_fence, list);
+		list_del_init(&fence->list);
+		if (fence->signal_callback) {
+			fence->signal_callback(rdev, fence->callback_data);
+		}
+	}
+}
+
 static void radeon_fence_destroy(struct kref *kref)
 {
 	unsigned long irq_flags;
@@ -152,6 +167,8 @@ int radeon_fence_create(struct radeon_device *rdev,
 	(*fence)->seq = 0;
 	(*fence)->ring = ring;
 	(*fence)->semaphore = NULL;
+	(*fence)->signal_callback = NULL;
+	(*fence)->callback_data = NULL;
 	INIT_LIST_HEAD(&(*fence)->list);
 
 	write_lock_irqsave(&rdev->fence_lock, irq_flags);
@@ -164,6 +181,7 @@ bool radeon_fence_signaled(struct radeon_fence *fence)
 {
 	unsigned long irq_flags;
 	bool signaled = false;
+	LIST_HEAD(siglist);
 
 	if (!fence)
 		return true;
@@ -179,10 +197,12 @@ bool radeon_fence_signaled(struct radeon_fence *fence)
 		signaled = true;
 	}
 	if (!signaled) {
-		radeon_fence_poll_locked(fence->rdev, fence->ring);
+		radeon_fence_poll_locked(fence->rdev, fence->ring, &siglist);
 		signaled = fence->signaled;
 	}
 	write_unlock_irqrestore(&fence->rdev->fence_lock, irq_flags);
+	radeon_fence_process_signaled(fence->rdev, &siglist);
+
 	return signaled;
 }
 
@@ -341,10 +361,12 @@ void radeon_fence_process(struct radeon_device *rdev, int ring)
 {
 	unsigned long irq_flags;
 	bool wake;
+	LIST_HEAD(signaled);
 
 	write_lock_irqsave(&rdev->fence_lock, irq_flags);
-	wake = radeon_fence_poll_locked(rdev, ring);
+	wake = radeon_fence_poll_locked(rdev, ring, &signaled);
 	write_unlock_irqrestore(&rdev->fence_lock, irq_flags);
+	radeon_fence_process_signaled(rdev, &signaled);
 	if (wake) {
 		wake_up_all(&rdev->fence_drv[ring].queue);
 	}
@@ -373,6 +395,25 @@ int radeon_fence_count_emitted(struct radeon_device *rdev, int ring)
 	return not_processed;
 }
 
+bool radeon_fence_set_signal_callback(struct radeon_fence *fence,
+				      void (*callback)(struct radeon_device *, void *),
+				      void *data)
+{
+	struct radeon_device *rdev = fence->rdev;
+	unsigned long irq_flags;
+	bool isset = false;
+
+	/* a readlock is suficient, cause this should be called only once */
+	read_lock_irqsave(&rdev->fence_lock, irq_flags);
+	if (fence->emitted && !fence->signaled) {
+		fence->signal_callback = callback;
+		fence->callback_data = data;
+		isset = true;
+	}
+	read_unlock_irqrestore(&rdev->fence_lock, irq_flags);
+	return isset;
+}
+
 int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
 {
 	unsigned long irq_flags;
@@ -413,7 +454,6 @@ static void radeon_fence_driver_init_ring(struct radeon_device *rdev, int ring)
 	atomic_set(&rdev->fence_drv[ring].seq, 0);
 	INIT_LIST_HEAD(&rdev->fence_drv[ring].created);
 	INIT_LIST_HEAD(&rdev->fence_drv[ring].emitted);
-	INIT_LIST_HEAD(&rdev->fence_drv[ring].signaled);
 	init_waitqueue_head(&rdev->fence_drv[ring].queue);
 	rdev->fence_drv[ring].initialized = false;
 }
-- 
1.7.7.6